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Q S Li

Publications and source records attributed to Q S Li.

47 records · Page 3Linked to original sources
PubMed1987

Immunoregulatory effect of neocortex in mice.

Immune responses were analyzed after neocortex ablation in mice. The neocortex ablations were performed in inbred mice on the left (ALN) or right hemisphere (ARN) separately. Two months later immunological parameters were tested. The results showed that the mitogenesis induced by Con A, natural killer cell (NK) cytotoxicity, production of IL-1 and IL-2 as well as the reactivity to IL-1 were all suppressed in ALN mice but stimulated in ARN mice compared to sham-operated controls. The primary antibody response to sheep red blood cells (SRBC) was also enhanced in ARN but not ALN mice. These results indicate that there may be a different regulatory effect on the immune system mediated by the different brain hemispheres, a phenomenon named lateralization of brain.

Animals↗
PubMed1986

[Nuclear DNA content in nasopharyngeal carcinoma (NPC) cells].

Cancer cell nuclear DNA content of 40 biopsy imprints of NPC was measured by Leitz MPV3 microspectrophotometer using scanning method. The pathological diagnosis and histological classification were done on the same specimens. By morphology, the poorly differentiated squamous carcinoma (34 cases) could be divided into four subtypes: ordinary nucleus type (14), spindle nucleus type (5), large and pleomorphic nucleus types (12 and 3). The first two types revealed a bimodal peak DNA histogram (2C and 4C) and slightly scattering toward the right to the 8C region in some nuclear DNA. The large nucleus type showed the bimodal peaks with a broad 4C and many nuclear DNA located in the 4C-8C range. The pleomorphic nucleus type appeared as multiple low peaks diffusing between 2C-12C. The vesicular nucleus cell carcinoma (3 cases) had a double peak DNA histogram similar to the ordinary nucleus type. The undifferentiated cell carcinoma (1 case) showed a broad unimodal peak DNA, ranging from 2C to 6C. The well differentiated squamous carcinoma (2 cases) had a double peak DNA, which was close to the normal diploid pattern but each peak was relative wide and a few DNA value located beyond the 4C region. The results indicate that DNA values showing a predominance of double peak histogram and diploid pattern imply the low grade malignancies in its biological behavior. In contrast, those showing the aneuploid and multiploid patterns in the majority of cancer cells point to the high grade malignancies. Hence, the supplementary DNA measurement of NPC cells can judge exactly the malignant degree of the tumor and provide evidence for prognosis.

Carcinoma, Squamous Cell↗
PubMed1981

Properties of the lysosomal apparatus during differentiation of cultured striated muscle cells.

A technique for the preparation of relatively pure myoblasts from chick primary culture is described. Cultured rat myogenic cells (L6) were plated and grown to provide three morphologically distinct cell populations: perfusion, postfusion, and nonfusion. Homogenates of L6 cells demonstrated two major peaks of proteolytic activity at pH 3.0 and 5.5. The activity could be partially inhibited by leupeptin or pepstatin. Differential centrifugation indicated significant acid hydrolase activity in the "H" fraction of prefused cells, which shifted to the "L" fraction after fusion of the cells. Two populations of lysosomes were resolved in the myoblasts and myotubes after isopycnic centrifugation in Percoll. The equilibrium densities were 1.044 and 1.060-1.068. Cells were incubated with several protease inhibitors. Only chloroquine caused a large inhibition of protein degradation.

Animals↗